Edited by Mary Rose de Valladares M.R.S. Enterprises, LLC ...

Figure­2: SEM image of ZnO nanorod
array (a) uncoated and (b) coated with
Fe 2 O 3 (CSIRO).
Figure­3: Model for carbon incor­
poration at a Ti vacancy site in rutile
(CSIRO).
At the Centre for Materials Research
in Energy Conversion of the University
of New South Wales (UNSW), the for­
mation of titanium vacancies in gas­solid
TiO 2 interface and the determination of
the rate of their propagation in the TiO 2
bulk lattice has been discovered. This
led to the successful development of
p­type TiO 2 at elevated temperatures of
up to 1050°C. This allows the prepa­
ration of p­type TiO 2 without the need
to incorporate foreign ions into the
TiO 2 lattice. They were found to form
a segregation­induced potential bar­
rier that retards charge transfer. TiO 2
quasi­metallic properties, which should
allow the construction of PEC cells with
enhanced charge transport. In addition,
surface sites have been
2
formation of the active complex between
H O and TiO 2 . This should pave the way
to process TiO 2 photoelectrodes with
enhanced performance through surface
engineering. Finally, segregation­in­
duced concentration gradients and the
related electrical potential barrier for
donor­doped TiO 2
Follow­on research aims to use the phe­
nomenon of segregation as the technol­
potential required for enhanced PEC
device performance.
At the University of Queensland,
transient photocurrent measurements
are being employed to elucidate the
charge carrier dynamics of the metal
oxide materials produced at CSIRO.
The method, also known as the “time­
strongly absorbed laser pulse to excite
electron­hole (e­h) pairs close to one
surface of the material in question. The
charge carriers are preferentially trans­
ported to a counter electrode by an
current transients over a broad range of
temperatures (–200°C to +50°C) yields
information about e and h mobilities as
well as trap distribution and activation
energy.
At the Atomic Energy Commission
(CEA), a new R&D program is being
established for the development of TiO 2 ­
based PEC photoelectrode materials,
related photocatalysis, and associated
processing techniques. Early work
has been focusing on the preparation
of WO 3 and mixed WO 3 /TiO 2 coatings
using magnetron sputtering and CVD
techniques.
At the National Centre for Scien­
progress was reported on the tailoring of
electronic and photophysical properties
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